sign in sign up
<<
Home , Kaumana Cave, Kazumura Cave, Lava tube

HAWAII TUBE , UNITED STATES 417

HAWAII CAVES, UNITED STATES The Hawaiian Islands are the world’s most important area for Kauai’s lava tube caves also are comparatively short and are the study of lava tube caves. A high proportion of the islands’ in rejuvenation-phase lava. Also present are three sizeable, much- voluminous lava flows passed through these tubes before they visited caves near sea level, which are either littoral caves in the solidified. The volcanology of the islands is primarily related to older lava or short lengths of very ancient lava tube caves eroded the mid-Pacific “hot-spot” magma plume or plumes, over which to the point where they have lost their distinguishing characteris- the ocean floor moves slowly northwestward, carrying the string tics of lava cooling and lava deposition. of islands with it. The islands’ predominant rock types thus Major lava tube caves exist on all the Big Island’s volcanoes become progressively older northwestward. except Kohala (which apparently has only erosional caves). With Kauai (the most northwesterly of the major islands) is primar- about 200 km mapped in several systems, the Ailaau flow ily composed of 5 to 7 million years old. In the middle of field of Kilauea is currently the world’s most important. the island chain, the oldest rocks of the island of Oahu are Here, alone has over 65.5 km mapped (at De- about 2 million years old. At the active southeast end, “The Big cember 2001), making it the longest lava tube cave in the world Island”—Hawaii Island proper—is still growing. About 95% of (Figures 1 and 2). Both and Hualalai volcanoes have it is pseudokarst. Only one of its five volcanoes is considered caves with more than 10 km mapped. extinct (Kohala), three are currently active or have recently been Mauna Kea volcano has recently been found to have several active (Mauna Loa, Kilauea, and Hualalai), and one older vol- shorter, unusually steep lava tube caves. Located in a gullied cano may or may not have shut down (Mauna Kea). In addition, rain forest, all are invaded intermittently by torrential high-load however, a poorly understood rejuvenation phase of volcanism streams, which have eroded them considerably. The largest is so produced significant lava tube caves on some of the older islands impacted that one school of thought considers it entirely an a few hundred thousand years ago. erosional phenomenon. In stark contrast, some of the lava tube East Maui has several extensive lava tube caves. One—Ka caves of the island’s dry leeward side contain thick deposits of Eleku Cavern—has been minimally developed for ecotourism. soluble volcanic minerals: gypsum, mirabilite, thenardite, and The most recent cave-forming flow on this island was about others. Even here, however, some caves show clear-cut deposi- 1790 AD, but its principal caves were formed in early Recent or tional evidence of invasion by occasional flash floods: a serious Pleistocene times. There is no complete agreement on the ages potential public health problem in populated, beach, and fishing of the various tube-forming flows on east Maui, and one—at areas. Unlawful dumping of raw sewage and toxic and hazardous the bottom of a deeply eroded gully—may be of Tertiary age. wastes in caves and dolines is very common in Hawaii. Contrary to many popular accounts, its famous Waianapanapa The Big Island’s Hawaii Volcanoes National Park, a World Caves are inland littoral caves, not lava tube caves. Heritage Site, is entirely pseudokarstic and contains many caves. With one possible exception, all the lava tube caves of Oahu Because of extensive early Hawaiian use of caves and also because are about two million years old. The longest is only about 100 of the rough, remote terrain, much of it is uninvestigated speleo- m. The spatter features in at least one of the caves appear to be logically. At the other extreme, 120 m of its famous Thurston brand new. Lava Tube is electrically illuminated, and is the world’s most visited lava tube cave. About 445 m long, it is a relatively feature- less upper-level corridor entered through a jameo (a lava collapse

Hawaii Lava Tube Caves: Figure 1. Outline map of the Kazumura Hawaii Lava Tube Caves: Figure 2. The main of Kazumura lava tube down the eastern slope of the Kilauea volcano on Hawaii’s Cave, which provides many kilometres of easy walking beneath the Big Island. eastern slope of Kilavea. (Photo by Tony Waltham).

5603$$000H 04-01-03 07:14:53 418 HAWAII LAVA TUBE CAVES, UNITED STATES sink / doline extending through more than one level of cave on top of a steep lava river—an oft-cited mechanism rarely seen (Halliday, 1993)). Permits are required for most of the other in Hawaii. A few contain notable lava dripstone, and some con- caves in the park. Some are notable for petroglyphs or for thickets tain Native Hawaiian fortifications and other evidence of use of lava dripstone. (Sinoto, 1992). The caldera of Kilauea volcano has both “ordinary” lava tube Hualalai is a much smaller volcano, but it also has large, caves and numerous small caves formed by subcrustal injection varied cave systems up to at least 11 km long. Its Laniakea Cave of fluid lava, followed by drainage. Some of these are largely was the first cave to be considered “celebrated” in Hawaii, but featureless tubes. Others are tubular but have sunken ceilings has been dreadfully neglected in recent decades. Others have that sagged while still plastic. Still others are hollow “whaleback” impressive lava falls, and some have parallel passages running lava tumuli several metres high and several times as long, or downslope. One Hualalai cave is especially notable for metre- long, sinuous hollow lava tumuli. A few are perimeter passages high “sand bars” of topsoil washed in by flash floods. around large “lava rises” with sunken centres (Walker, 1991). The lava flow which formed Maui’s 2724 m Ka Eleku Cavern Others resulted from drainage of sheet-flow units (Hon et al., is much blacker and was much more viscous than most of those 1994). Many of the caves in the caldera are hyperthermal and on the Big Island. In Ka Eleku, lava characteristi- require special exploration techniques. cally are so dark and massive that commonly it is difficult to Also within Hawaii Volcanoes National Park, the Ailaau vent distinguish them from the walls of the cave. was the supply source for Kazumura and many other major caves WILLIAM R. HALLIDAY in its flow field. It is about 350 years old. Most of the actual vent structure collapsed into Kilauea Iki crater, which developed Works Cited more recently. Kazumura Cave now begins outside the park; part Halliday, W. 1993. Kaluaiki and Thurston Lava Tube: an of its upper end was unknowingly destroyed by state highway unrecognized jameo system? In Proceedings of the 3rd construction. It originally extended from a point near Thurston International Symposium on Vulcanospeleology, Bend. OR, July 30– Lava Tube to the 65-m contour near the ocean. Its remaining August 1, 1982, edited by W. Halliday, Seattle: International passages still have a unique unbroken descent of 1101 m in a Speleological Foundation Hon, K. et al. 1994. Emplacement and inflation of pahoehoe sheet linear distance of 34 km. Its overall floor plan is that of a long flows. Geological Society of America Bulletin, 106: 351–70 crooked pole with small bunches of spaghetti strung along it at Sinoto, Y. 1992. Hawaiian use of lava tube caves and shelters. In intervals. Many entrances are present, with and without exten- Proceedings 6th International Symposium on Vulcanospeleology, sive secondary ceilings that form multiple levels. The upper, Hilo, HI, August 1991, edited by G.T. Rea, Huntsville, Alabama: steeper part tends to be high and narrow, with some cutbanks National Speleological Society and slip slopes that show downcutting by flowing lava. Lava Walker, G. 1991. Structure, and origin by injection of lava under falls up to 15 m high are present, some with large plunge-pool surface crust, of tumuli, “lava rises”, lava rise pits”, and “lava chambers at their bases. Farther downslope, the cave characteris- inflation clefts” in Hawaii. Bulletin of Volcanology, 52: 546–58 tically is wide and comparatively low. Innumerable individual Further Reading rheogenic and spatter features are present, mostly undescribed. Many are formed of a reddish or brown late-stage lava which Calvari, S. & Pinkerton, H. 1998. Formation of lava tubes and extensive flow fields during the 1991–93 eruption of Mt. Etna. contrasts with the dark grey tube linings. About one-third of Journal of Geophysical Research, 103: 27 281–301 the cave is floored by breakdown, but two sections with long Ellis, W. 1823. Journal of William Ellis. Reprinted 1963, Honolulu: lengths of walking passage have undergone minor development Advertiser Publishing for ecotourism. Forti, P. (editor) 1998. Proceedings, 8th International Symposium is a county park in a suburb of the city of on Vulcanospeleology. Nairobi, February 1998. International Hilo. Its more accessible sections are a very popular local attrac- Journal of , 27B (1–4): 1–163 tion. This cave is in a 1881 Mauna Loa flow which nearly Greeley, R. 1987. The role of lava tubes in Hawaiian volcanoes. In reached the ocean at Hilo. In 2000, a hydrostatic overload blew Volcanism in Hawaii, edited by R.W. Decker, T.L. Wright & out a segment of its roof, on the edge of a suburban street. It P.H. Stauffer, Washington: Government Printing Office (US is an intermittent but important part of Hilo’s system, Geological Survey Professional Paper 1350) and initial hydrological studies are under way. Exploration and Halliday, W. editor. 1993. Proceedings, 3rd International Symposium on Vulcanospeleology. Bend, OR. July 30–August 1, 1982. Seattle: study of remote portions of this cave have been hampered by International Speleological Foundation illegal dumping of used diapers, garbage, and other hazardous Kauahikaua, J. et al. 1998. Observations on basaltic lava streams in substances. tubes from Kilauea volcano, island of Hawaii. Journal of Located on the Southwest Rift Zone of Mauna Loa volcano, Geophysical Research, 103: 21 303–323 the Kula Kai cavern system contains the island’s best-known Kirch, P.V. 1985. Feathered Gods and Fishhooks: An Introduction to . One of its caves is 16 km long. Because of the pres- Hawaiian Archaeology and Prehistory,Honolulu: University of ence of soluble minerals, cavern walls here tend to be much Hawaii Press lighter-coloured than most caves in Hawaii, and the cave’s spel- Macdonald, G., Abbott, A. & Peterson, F. 1983. Volcanoes in the eogenesis appears to be unusually unconstrained by confining Sea: The of Hawaii, 2nd edition. Honolulu: University of lava, with a tendency to form mazes. Hawaii Press The northwest and southwest slopes of Mauna Loa volcano Rea, G.Y. (editor) 1992. Proceedings, 6th International Symposium on Vulcanospeleology, Hilo, HI, August 1991,Huntsville, Alabama: contain numerous shorter caves, some of large volume. Their National Speleological Society individual characteristics appear to be determined by the param- eters of the flows that contain them. One is a notable demonstra- See also Hawaiian Islands: Biospeleology, Volcanic Caves, tion of formation of a lava tube cave by wedging of crusts floating Vulcanospeleology: History

5603$$000H 04-01-03 07:14:53